1. Field of the Invention
The present invention relates to an electron emission source, its method of fabrication, and an electron emission device using the electron emission source. More particularly, the present invention relates to an electron emission source having reduced a carbon-based material degradation during sintering, its method of fabrication, and an electron emission device using the electron emission source.
2. Description of the Related Art
Electron emission devices are displays that create images by emitting light by collision of phosphors in a phosphor layer of an anode plate with electrons emitted from electron emission sources of a cathode under an electric field generated when a voltage is supplied to the anode and the cathode.
Carbon-based materials, including Carbon Nano-Tubes (CNTs) with good electron conductivity, have advantages such as good conductivity and field enhancement effect, a low work function, a good field emission property, a low driving voltage, and device fabrication over a large area. Therefore, carbon-based materials are expected to be ideal electron emission sources for electron emission devices.
CNT-based electron emission sources can be fabricated by growth of CNTs on a substrate using, for example, Chemical Vapor Deposition (CVD) or a paste method using a CNT-containing, electron emission source-forming composition. With respect to the paste method, there is an advantage in that electron emission sources can be fabricated over a large area at a low cost. For example, a CNT-containing, electron emission source-forming composition is discussed in U.S. Pat. No. 6,436,221.
A conventional electron emission source fabrication method using a carbon-based material involves sintering a composition for forming electron emission sources. The sintering process is performed under an inert gas atmosphere to prevent electron emission degradation due to thermal decomposition of a carbon-based material such as CNTs.
However, sintering under an inert gas atmosphere cannot ensure a sufficient removal of organic materials, etc. used for fabricating the electron emission sources, leading to degradation in electron emission capability. In particular, when a lead-containing frit component is used in the fabrication of electron emission sources, thermal decomposition of CNTs occur. As a result, as an electron emission device fabrication process proceeds, electron emission degradation can worsen.